#!/bin/bash
# @file pane-launch.sh
# @description Server mode, one Linux user per account (S3): installed as
# /opt/agenthub/libexec/pane-launch. A member's pane starts as
# `pane-launch <launch file>`: the dashboard creates the session AS the member
# through sudo, and sudo logs its whole command line — so the pane's
# environment (a pane token, a pool account's token) and its argv (the prompt)
# are not in that command line but in the launch file, which `write-as`
# wrote as the member (0600) from stdin. This reads it, deletes it, exports
# the environment and execs the command; no shell ever parses a value.
#
# The file is NUL-separated: the number of environment entries, the
# NAME=value entries, then the argv (none = a login shell). Every pane starts
# at a lower CPU/IO priority, Claude's commands as the kernel's first OOM pick.
# @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
set -eu
f=${1:?usage: pane-launch <launch file>}
mapfile -d '' -t parts <"$f"
rm -f -- "$f"
n=${parts[0]}
[[ "$n" =~ ^[0-9]+$ ]] || { echo "pane-launch: malformed launch file" >&2; exit 2; }
for kv in "${parts[@]:1:n}"; do
  [[ "$kv" =~ ^[A-Za-z_][A-Za-z0-9_]*= ]] || { echo "pane-launch: bad variable" >&2; exit 2; }
  export "$kv"
done
# A member's pane shares the 4-core box with the dashboard and every other
# member, so it runs at a lower CPU/IO priority (a member cannot take the
# nice back: that needs root). Memory (11-02: 36 sessions plus test runs
# filled RAM and swap, and the box froze until a hard reset): the unit caps
# its cgroup below RAM (install-system.sh), and inside it the kernel kills
# by oom_score_adj — the dashboard and tmux at the unit's -100, an AI session
# at 300, a Terminal tab at 800, and every command Claude runs at 1000
# through CLAUDE_CODE_SHELL_PREFIX=tool-run. So a runaway command dies and
# the session that holds the conversation is told why; a member who lowers
# their own value can go no lower than -100.
renice -n 10 -p $$ >/dev/null 2>&1 || true
ionice -c 2 -n 7 -p $$ >/dev/null 2>&1 || true
TOOL_RUN=/opt/agenthub/libexec/tool-run
[ -x "$TOOL_RUN" ] && export CLAUDE_CODE_SHELL_PREFIX="${CLAUDE_CODE_SHELL_PREFIX:-$TOOL_RUN}"
# Vitest ≤ 3 starts one worker per core by default and these override the
# config; a member may set their own in the pane.
export VITEST_MAX_THREADS="${VITEST_MAX_THREADS:-2}" VITEST_MAX_FORKS="${VITEST_MAX_FORKS:-2}"
argv=("${parts[@]:n+1}")
if [ ${#argv[@]} -eq 0 ]; then
  echo 800 >/proc/self/oom_score_adj 2>/dev/null || true
  exec -l "${SHELL:-/bin/bash}"
fi
echo 300 >/proc/self/oom_score_adj 2>/dev/null || true
exec "${argv[@]}"